Bubble generator

ABSTRACT

THIS DISCLOSURE INCLUDES A SOAP BUBBLE GENERATOR ADAPTED TO GENERATE A CONTINUOUS, CONTROLLABLE STREAM OF SOAP BUBBLES IN RESPONSE TO A STREAM OF AIR IN WHICH THE DEVICE IS PLACED, AS WHEN MOUNTED ON A BICYCLE. THE DEVICE INCLUDES A SPECIALLY CONSTRUCTED BUBBLE RING WHICH IS SUPPORTED CENTRALLY WITHIN THE OUTLET END OF A TUBE WHICH ALSO IS OPEN AT ITS FORWARD END TO INGEST AND DIRECT AIR FLOW REARWARDLY TOWARD AND THROUGH THE RING ALONG A SUBSTANTIALLY LAMINAR PATH. THE BUBBLE RING IS OF HOLLOW, ANNULAR CONSTRUCTION, THE HOLLOW OF THE RING BEING IN CONSTANT COMMUNICATION WITH A SOURCE OF SOAPY LIQUID ADAPTED TO FORM SOAP BUBBLES. THE RING ALSO INCLUDES A NUMBER OF OUTLET ORIFICES FORMED AT ITS REARWARD SURFACE TO PERMIT THE SOAPY LIQUID TO FLOW ABOUT THE RING AND FORM A FILM OVER THE OPENING IN THE RING. THE AIR FLOWING THROUGH THE TUBE   AND THE RING GENERATES A CONTINUOUS STREAM OF BUBBLES WHICH ARE EMITTED FROM THE RING, THE SOAPY LIQUID FLOWING CONTINUALLY TO THE RING AS THE BUBBLES ARE GENERATED. CONTROL OF THE BUBBLE FORMATION IS PROVIDED BY A SEALING PAD WHICH IS MOVEABLE BY THE OPERATOR FROM A CLOSED POSITION ABUTTING THE REARWARD FACE OF THE RING TO A REMOTE POSITION THUS PERMITTING THE FLOW OF AIR AND SOAPY FLUID TO BE CONTROLLED.

Dec. 14, 1971 v. s. I r-:RMAN 3,626,631

BUBBLE GENERATOR Filed May 1, 19701 2 Sheets-Sheet 1 1MM/Saab Dec. 14, 1971 v. s. LERMAN BUBBLE GENERATOR 2 Sheets-Sheet 2 Filed May l, 1970 www United States Patent O 3,626,631 BUBBLE GENERATOR Victor S. Lerman, 149 Essex St., Malden, Mass. 02148 Filed May 1, 1970, Ser. No. 33,729 Int. Cl. A63h 33/28 U.S. Cl. 46-7 26 Claims ABSTRACT F THE DISCLOSURE This disclosure includes a soap bubble generator adapted to generate a continuous, controllable stream of soap bubbles in response to a stream of air in which the device is placed, as when mounted on a bicycle. The device includes a specially constructed bubble ring which is supported centrally within the outlet end of a tube which also is open at its forward end to ingest and direct air flow rearwardly toward and through the ring along a substantially laminar path. The bubble ring is of hollow, annular construction, the hollow of the ring being in constant communication with a source of soapy liquid adapted to form soap bubbles. The ring also includes a number of outlet orifices formed at its rearward surface to permit the soapy liquid to flow about the ring and form a film over the opening in the ring. The air llowing through the tube and the ring generates a continuous stream of bubbles which are emitted from the ring, the soapy liquid owing continually to the ring as the bubbles are generated. Control of the bubble formation is provided by a sealing pad which is moveable -by the operator from a closed position abutting the rearward face of the ring to a remote position thus permitting the flow of air and soapy uid to be controlled.

BACKGROUND OF THE INVENTION This invention relates to soap bubble generating devices, and, more particularly, to an improved device for generating a continuous stream of bubbles in response to a continuous flow of air. The bubble generator may be used as an amusement device or as a smoke simulator on a bicycle in which the bubble stream is generated in response to forward movement of the bicycle.

Generating a stream of soap bubbles by blowing or directing air through a ring supporting a high surface tension soapy film, of course, has for a long time been ernployed as an amusement device for children. The technique employed largely has been to dip a rigd supporting ring in the soapy solution so that the ring picks up a quantity of the solution which forms a lilm over the opening of the ring. An air stream then is directed through the ring as by blowing or waving the ring through the air to form the stream of bubbles.

In some instances, a mechanized arrangement has been provided in which one or more rings are mounted for repetitive dipping into and out of a bath of the soapy solution and then into the air stream. In these arrangements, however, the supply of soapy fluid to the ring :iS limited to the quantity which the ring can pick up from the simple dipping process. This, in turn, limits the duration of the bubble stream. The ring must be dipped again in order to replenish the supply of soapy solution. Additionally, because this technique involves repetitive dipping of the bubble ring into the soap solution reservoir, the tank which defines the reservoir must have a relatively large opening through which the ring and its supporting structure may be passed. This is undesirable, particularly when the device is to be used in an environment in which it is likely to be jarred and subjected to repeated shocks and vibrations. For example, if a device having an enlarged opening formed in its soap fluid reservoir if it were mounted on a bicycle the likelihood of a substantial 3,626,631 Patented Dec. 14, 1971 ice portion of the soapy liquid being spilled from the tank would be considerable. This is both messy and requires that the tank be refilled with a relatively high degree of frequency.

In general, the prior mechanized devices having moving parts for loading and reloading the bubble forming rings with soapy solution must be operated continuously and smoothly in order to sustain a continuous bubble generating process. It is among the primary objects of the invention to provide a soap bubble generator which requires no moving parts in order to load or reload the bubble forming ring with soapy fluid.

SUMMARY OF THE INVENTION This invention overcomes the above difficulties in that it includes no moving parts for the continuous bubble generating process. The device includes a construction Iwhich feeds the soapy liquid continuously and regularly to the stationary bubble forming ring. The tank in which the soapy liquid is stored is enclosed fully, except for an air hole, so that it is virtually impossible for any of the soap solution to spill from the tank.

In brief, the device includes a number of parts which are connected to each other in an integral unit which, as in the illustrative embodiment, may be mounted to a bicycle or the like. The device includes a hollow ring which is mounted in a xed position and in a plane that is substantially normal to the air stream. The hollow of the ring is in direct communication with the liquid reservoir at all times. The rear face of the ring has a plurality of rearwardly opening holes which permit the soapy lluid to flow from the overhead tank through the ring and onto the rear face of the ring to form a thin film over the annular opening defined by the ring. The rear face of the ring is of a concave configuration which, as described more fully herein, is effective to induce the flow of the soapy fluid from the overhead tank in response to the air fiowing through and about the bubble generating ring.

The ring is located centrally in the rear end of a tube. The front end of the tube faces forwardly and is open to receive the air flow as when mounted on a bicycle 0r other vehicle. The forward end of the tube ingests air and guides the air rearwardly toward the bubble forming ring in a substantially laminar flow. Additionally, the tube may be tapered rearwardly to increase the velocity of the air flowing across and through the ring. This effectively lowers the static pressure about the ring, which, in turn, enhances the flow of soapy fluid from the overhead reservoir. In the preferred embodiment, the fluid also tends to ow under the effect of gravity because the tank is mounted overhead.

The device also includes a closure pad which is pivotable between a closed position in which the pad is in flush abutment with the rear, outlet face of the bubble forming ring to preclude flow of the soapy iluid. The pad normally -is biased in this closed position and may be moved to a remote position to expose the rear, outlet face of the ring and thus permit development of the bubble stream. Movement of the closure pad between these positions is controlled by an appropriate control in easy reach of the operator. The device also includes a stop member which is associated with the closure pad to lock the pad in a slightly spaced relation to the rear face of the ring when the device is not in use. By storing the device in this configuration, any chance of the pad sticking to the rear face of the ring, as by the solution evaporating and leaving a sticky soap residue, is avoided. Additionally, the formation of a soapy crust on the pa-d during non-use also is avoided.

Among the primary objects of the invention is to provide a soapy bubble generator adapted to emit a continuous stream of soap bubbles without employing moving parts to sustain the continuous emission of the bubbles.

A further object of the invention is to provide a soapy bubble generator in which a soapy liquid is caused to liow continuously from a liquid reservoir to a bubble forming ring in response, at least in part, to the fiow of air through the ring.

A further object of the invention is to provide a continuous soap bubble generator having a hollow ring fixed in place and disposed substantially normally to the air stream in which soapy liquid may be delivered to the bubble ring without requiring repetitive dipping of the ring into a bath of soapy solution.

Still another object of the invention is to provide a continuous soap bubble generator which includes a fully enclosed reservoir for storing a supply of soapy liquid and in which the likelihood of any of the liquid spilling from the reservoir is minimized. The tank includes no enlarged openings through which the soapy fiuid might leak.

A further object of the invention is to provide a continuous soap bubble generator in which the emission of soap bubbles may be controlled.

Yet another object of the invention is to provide a device for generating a continuous stream of soap bubbles in response to air fiow through the device and which includes an arrangement for directing the air stream at all times in substantially laminar liow in a direction which is substantially normal to the plane in which the bubble forming ring is disposed.

DESCRIPTION OF THE DRAWINGS The above and other objects and advantages of the invention will be understood more fully from the following detailed description thereof, with reference to the accompanying drawings wherein:

FIG. 1 is a side elevation of the device;

FIG. 2 is a rear, end view of the device with the closure pad in its downward, open position to expose the rear face of the bubble generating ring;

FIG. 3 is a fragmented, sectional view of the device similar to FIG. l showing the internal construction of the bubble forming ring;

FIG. 4 is a section through the closure pad and its mounting arm; and

FIG. 5 is a rear view of the closure pad and its supporting mechanism as viewed along the line 5--5 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. 1 the device includes an air tube which is open both at its forward end 12 and rearward end 14. The tube 10 is formed integrally and securely to a bracket 16 which depends from the tube 10 and includes a hole 18 by which the device may be mounted to a suitable support, as the frame of a bicycle. A tank 20` is mounted to the top of the air tube 10. The various elements of the device may be fabricated from sheet metal and fastened together by conventional techniques las soldering, brazing, etc. The tank 10 may be of cylindrical design or other appropriate shape and includes a filling spout 22 which extends upwardly from the body of the tank 20. The filling spout is covered by a cap 24 which has a small vent hole 26 to prevent the interior of the tank 20 to be maintained at atmospheric pressure.

The device is mounted so that the forward end 12 of the tube 10 ingests air and directs the air, in substantially laminar flow, rearwardly toward and through the rearward end 414 of the tube 10. The bubble-forming ring, indicated generally by the reference character 28 is supported within the rearward end `14 of the air tube 10, preferably in central alignment with the tube 10, so that it lies substantially within a plane that is normal to the direction of air fiow through the tube 10. The ring 28 is supported by a hollow tube 30 which is fastened, at its 4 upper end, to the lower wall 32 of the tank 2li. The tube 30 is effective to communicate the soapy liquid from the tank to the bubble forming ring 28.

As shown in FIG. 3, the bubble forming ring 28 includes an internal annular chamber 34 which is in communication with the hollow tube 30 to receive the soapy liquid from the tube 30. The ring 28 may be formed from any number of suitable materials such as brass, and, preferably is of a two-piece construction consisting of a main body portion 36 in which is formed the rearward face 38 and hollow annular chamber 34 and a capping ring 40 which is sealed to the forward face of the main body portion 36 to enclose and define the annular chamber 34.

In the preferred embodiment of the invention, the rearward face 38 of the bubble forming ring 2.8 is concave and includes a number of outlet orifices 42 which open rearwardly through the concave rearward face 38` of the ring 28. Although the outlet orifices 42 may be circumferentially spaced fully about the concave annular rearward face it is preferred to provide the orifices only in the upper region of the bubble forming ring 28.

As described more fully below, during operation the soapy liquid iiows regularly and continuously into the annular chamber 34 of the ring and then rearwardly through the orifices 42. The soapy liquid flowing outwardly through the orifices 4,2 fiows downwardly within the concave channel in the rearward face 38 of the ring 28 to fill the concave channel completely. The device then is actuated to draw some of the soapy liquid within the concave rearward face 38 inwardly within the inner opening 44 defined by the inner surface 46 of the ring 28 in a thin film which covers completely the opening 44 and which is self-supporting by reason of its surface tension. Once the film is formed within the opening 44, the air fiowing rearwardly through the air tube 10 will form a bubble as it passes through the inner opening 44 of the ring 28. The continuous fiow of soapy liquid from the tank to the concave rearward face 38 of the ring 28 provides a steady and regular continuous replenishment of the film about and within the inner opening 44. This enables a continuous stream of bubbles to be formed as the air continues to flow through the air tube 10 and opening 44 of the ring 48. The bubble formation will be continuous as long as the air fiow and supply of soapy liquid is uninterrupted.

The formation of the soapy film within the inner opening 44 of the ring 28 is initiated by a pad, indicated generally by the reference character 48 which is moveable, at the control of the operator, between the position shown in FIG. 2 in which the pad 48 is remote from the bubble forming ring 28 and a position shown in FIG. l in which the pad `bears directly against, and in sealing relation to the concave rearward face 38 of the ring 218. In order to prime the device, the pad 48 is brought to bear against the rearward face 38 and into contact with the soapy liquid within the concave channel. The adhesive, wetting characteristics of the soapy liquid cause the liquid within the concave channel to wet the surface of the pad 48 so that when the pad thereafter is moved to its remote position it will draw some of the liquid away from the ring and initiate the formation of the film. As the pad is drawn away from the ring to draw out the soapy film the film then tends to snap back toward the ring to locate the film within the opening 44 in the ring 28.

As the film is being formed, withdrawal of the pad also opens the orifices 42 to the atmosphere which causes the soapy liquid to flow in a regular stream from the tank 20 to the rearward face 3S of the bubble forming ring 28. Thus, after the pad 48 has been withdrawn to initiate the formation of the soapy film, the soapy liquid will fiow continuously and regularly to replenish the soapy liquid in the concave rearward face 38 of the ring 28 to permit subsequent repetitive formation of the film.

The film is regenerated quite rapidly which permits the bubbles to be formed in a rapid, continuous sequence. Indeed, when the device is used, as on a bicycle, the fbubbles appear to stream rearwardly from the device in endless multitudinous series. The regeneration of the film and bubble formation virtually is impossible to follow visually.

As shown more clearly in FIGS. 4 and 5, the pad 48, itself, includes an inner supporting member 50` which is covered, at least at its forwardly facing, ring-engaging surface with a substantially flat, resilient membrane 52. The membrane 52 should be formed from a material which may be wetted easily by the soapy liquid so that the liquid may adhere to the membrane and be drawn rearwardly to initiate formation of the soapy lm as the pad 48 is withdrawn to its remote position. For example, the membrane may be formed from a thin sheet of rubber. In the preferred embodiment of the invention the membrane is defined by part of a rub-ber balloon which is slipped about the inner support member 50 with a portion of the balloon being stretched over and about the forwardly facing side of the support member 50i.

The support member 50 is of circular configuration having a rear Wall 56, a forwardly extending peripheral flange 58 and an inner, concentric, forwardly extending `flange 60. The membrane or resilient portion of the rubber balloon 54 thus is supported from behind by the concentric circle defined by the flanges '58, 60` so that the annular region of the, membrane 52 which spans the annular space between the flanges 58, 60 is unsupported and may be urged resiliently into this annular space within the support member S0.

The langes 58, 60 are dimensioned, respectively, so that when the pad 48 is brought to bear against the rearward face of the ring 218, the outer peripheral flange 58 will include the outer diameter of the ring 218 and the inner flange 60 will be included within the inner opening 44 of the ring 28. This arrangement permits the resilient, unsupported annular portion of the membrane 52 to be urged firmly and resiliently against the rearward face 38 of the ring 28 to seal completely the rearward face 38. Additionally, it is preferred to provide a pair of vent holes 6-2, 64 in the rear wall 'S6 of the inner support member '50 and within each of the spaces defined by the flanges '5-8, `60 so that when the rubber balloon 54 is wrapped about the support member excess air cannot be trapped between the support member and the membrane which might tend to cause the membrane to bulge. The vent hole 62, 64 insure that the ring engaging membrane 52 will lie flat against the supporting edges of the flanges 58, 60 of the support member 50.

As described below, the pad 48 is biased toward the bubble forming ring 218 so that the pad normally closes and seals the concave rearward face 318 of the ring 28. The pad 48 is supported at the end of an arm 66 which, in turn, is secured rigidly to the end of a clevis defined by the spaced clevis plates 68. The clevis plates 68, in turn, embrace and are pivoted to the rearward end of the bracket 16 by a pin 10. The pad 48 is mounted to the free end of the arm 66 by means of a bushing 72 which is secured to the end of the arm 66 and which receives a rearwardly extending lug 74 formed integrally with the inner support member 50. The inner support member 50 is retained in place on the end of the arm screw 7.6 which is screwed into the end of the lug 74 and which has a head larger than the diameter of the bushing. The lug preferably is dirnensioned so that it fits somewhat loosely within the bushing and may have slight limited freedom therein. This enables the pad 48 to orient itself so that the membrane 52 can seat itself firmly against the rearward face 3-8 of the ring 2-8.

The pad 48, arm 66 and clevis plates 68 thus pivot in unison about the pin 70 between the ring-engaging position and a remote position as shown. The pad 48 is biased in the ring engaging position by means of an endless elastic band 78 which is wrapped about the forward end of the bracket 16 and is retained within a notch 80 in the bracket. The rearwardly extending portion of the endless elastic band passes over the clevis plates and are retained within grooves 82 formed in each of the clevis plates 68. The region of the clevis plates 68 in which the grooves 82 are formed which engages the elastic band 78 preferably are arcuate so that the band may wrap about the grooves 82 smoothly. The rearward end of the endless elastic band 78 is wrapped about the arms 66 and is retained in engagement with the arms 66 by a notch 84 formed in the rear edge of the arm 66.

Operation of the pad to move it between the above positions may be controlled by a string 86 which is fastened to the clevis below the level of the pin 70 and which extends forwardly to the location where the string may be pulled by the operator. When controlled in this manner an eyelet 88 preferably is formed at the forward lower end of the air tube 10 to receive and guide the string 86. When used on a bicycle the forward end of the string may simply be gripped by the rider or may be connected to a lever or other operating control mounted to the bicycle. In the preferred embodiment the string 88 is tied to a pin 90 which is secured to the lower rearward corner of the clevis plates 68. This pin 90 also serves as a stop to limit the extent of pivotal movement of the pad 48 and its supporting structure. The clevis cannot be rotated past a position in Which the pin 90 engages the underside of the bracket 16.

The device also includes an arrangement for locking the clevis in a position such that the pad 48 is spaced partly from the bubble forming ring 28. This is desirable when the device is not in use and the tank is empty. By spacing the pad `48 and, therefore, the ring engaging membrane 52 from the ring the useful life of the membrane 52 is prolonged in that it will not bear continually against the rearward face 38 of the ring 28. This arrangement includes a locking brace which consists essentially of a at finger 92 which is pivoted at one end by the pin 94 to one of the clevis plates 68. The other, free end of the finger is formed in a V-shaped notch 96 which is engageable with the rearward edge of the air tube 10 to preclude the clevis and pad 48 from pivoting forwardly into engagement with the ring 28. The finger 92 is raised into the tube engaging position only when it is desired to lock the pad 48 in that position. The elastic 78 biases the pad 48 and clevis plates 68 forwardly which retains the finger 92 in its locked configuration.

In operation, the air tube 10 ingests air and directs the air a substantially laminar flow pattern toward the bubble forming ring to form the bubbles as described above. Although the substantially laminar flow is' desirable in that it tends to enhance the regularity and continuity of the generated bubble stream, it is not essential strictly in order to employ the invention. Some turbulent flow of air can be tolerated and the results can still be quite satisfactory. The air tube 10 is preferable when the device is used on a bicycle in which relatively sharp turns may be made. The tube 10 guides the air in substantially laminar flow normal to the plane of the bubble forming ring 28 irrespective of the change in direction of the vehicle.

Another aspect of the invention resides in the rearward conical taper of the air tube 10 which effectively reduces the cross section of the flow area for the air as it flows rearwardly toward the bubble forming ring 28. This tends to increase the velocity of the rearwardly directed air stream to a maximum when it reaches the rearward end 14 where the bubble forming ring 28 is located. The increased velocity of the air iiows over the ring 28 reduces the static pressure in the region of the ring. This in turn, increases the pressure differential between the outlet orifices 42 in the ring 28 and the interior of the tank 20 which is maintained substantially at atmospheric pressure at all times by reason of the vent hole 26 formed in the cap 24.

This differential in pressure is enhanced further by the difference in elevation between the orifices 42 and the liquid in the tank 20 which provides a static pressure head in addition to that formed in response to the reduced pressure of the fiowing air about the ring 28. The pressure differential causes the soapy liquid to fiow continuously from the tank to and out of the ring thus providing a constant supply of soapy liquid to regenerate repetitively and rapidly the lm necessary to form the bubbles. Thus, the rate of liow of the soapy liquid 1s dependent, in part, on the velocity of the air flowing through the air tube which, in turn, varies as the velocity of the bicycle. When the air speed is increased, the bubbles will be formed at an increased rate. This requires an increased flow of liquid to sustain repetitive and automatic regeneration of the film. The device is automatic in that as the volcity of the air through the tube 10 is increased, the increased pressure differential resulting from the drop in static pressure of the air about the ring will cause the soapy liquid to flow to the ring at the increased rate necessary to sustain continuous bubble formation.

Thus, the invention provides an arrangement and technique for generating and sustaining a continuous sequence of bubbles without the use of any special moving parts for dipping repetitively the bubble forming ring in the soapy solution. The device functions continually as long as the air stream and supply of soapy liquid are continued. Although the device has been described as being used primarily as an amusement for attachments to a bicycle it may be employed in any other environment in which it is desirable to provide a continuous stream of soap bubbles.

It should be understood that the foregoing description is intended merely to be illustrative of the invention and that other modifications and embodiments thereof will be apparent to those skilled in the art without departing from its spirit.

Having thus described the invention what is claimed 1. A device for generating bubbles from a film-forming liquid, continuously and repetitively comprising:

a ring adapted to be wetted by said liquid and to support said liquid in a film across the opening defined by said ring;

means for supporting said ring in a position in which a stream of air may be directed toward said ring along a path which is substantially normal to the plane in which said ring supports said film whereby said air stream may cause said supported film to be blown into a bubble and discharge from said ring along said direction substantially normal to the plane in which said ring supports said film; and

means for communicating said liquid from a source thereof to the surface of said ring in a steady, continuous flow and at a tiow rate which is at least sufiicient to replenish the quantity of said liquid which is used in the formation of said bubbles, said replenishment being sufficient to permit continuous regeneration of said film within said ring after each bubble is discharged whereby said bubbles will be generated and emitted from said ring continuously in response to continuation of said air stream.

2. A device as defined in claim 1 wherein said ring includes a rearward, downstream face adapted to support an endless bead of said liquid, said film being formed from the liquid in said bead;

said means for communicating said liquid from said source thereof being arranged to direct said liquid to said rearward, downstream face of said ring.

3. A device as defined in claim 2 wherein said downstream face is concave.

4. A device as defined in claim 3 wherein said means for communicating said liquid from said source thereof to said rearward concave face of said ring comprises:

Cil

said ring being formed of hollow construction defining a hollow chamber therein;

means for directing said liquid from said source thereof into the chamber within said ring; and

orifice means formed in the rearward, downstream face of said ring to enable said liquid to flow from the internal chamber of said ring into the concave channel formed at the downstream face of said ring.

5. A device as defined in claim 4 further comprising:

said orifice means being located in the upper region of said ring.

6. A device as defined in claim 5 further comprising:

means mounting said source of liquid at an elevation which is above said ring whereby said liquid may flow, gravitationally, continuously toward said ring.

7. A device for generating bubbles from a lm-forming liquid, continuously and repetitively comprising:

a ring adapted to be wetted by said liquid and to support said liquid in a film across the opening defined by said ring;

means for supporting said ring in a position in which a stream of air may be directed towards said ring along a path which is substantially normal to the plane in which said ring supports said film whereby said airstream may cause said supported film to be blown into a bubble and discharged from said ring,

said ring being of hollow construction to define a chamber therein, said ring having orice means opening from said hollow chamber in a rearward, downstream direction;

means for communicating said liquid from a source thereof to the surface of said ring in a steady, continuous fiow and at a fiow rate which is at least sufficient to replenish the quantity of said liquid `which is used in the formation of said bubbles, said replenishment being sufficient to permit continuous regeneration of said film within said ring after each bubble is discharged whereby said bubbles will be generated and emitted from said ring continuously in response to continuation of said airstream, said communicating means comprising means for directing said liquid into said hollow chamber of said ring whereby liquid may fiow through said hollow ring and outwardly downstream through said orifice means.

8. A device as defined in claim 7 wherein said orifice means is formed only in the upper region of said ring.

9. A device as defined in claim 7 wherein said source of said liquid is mounted at an elevation above that 0f said ring whereby said liquid may flow, gravitationally and continually from said source to said ring.

l0. A device as defined in claim 9 wherein said means for supporting said ring in said vfixed position comprises:

a tube secured to said tank and depending therefrom;

means mounting said ring to the lower end of said tube, said tube effecting communication between said tank and said ring.

11. A device for generating bubbles from a film-forming liquid, continuously and repetitively comprising:

a ring adapted to be wetted by said liquid and to support said liquid in a film across the opening defined by said ring;

means for supporting said ring in a position in which a stream of air may be directed toward said ring along a path which is substantially normal to the plane in which said ring supports said film whereby said air stream may cause said supported 'film to be blown into a bubble and discharged from said ring;

means for communicating said liquid from a source thereof to the surface of said ring in a steady, continuous fiow and at a flow rate which is at least sufficient to replenish the quantity of said liquid which is used in the formation of said bubbles, said replenishment being suicient to permit continuous regeneration of said film within said ring after each bubble is discharged whereby said bubbles will be generated and emitted from said ring continuously in response to continuation of said air stream;

means for priming said ring including a pad adapted to be wetted by said liquid; and

means mounting said pad for -movement toward and away from the rearward downstream surface of said ring to engage said downstream surface and be wetted by liquid on said downstream surface whereby subsequent movement of said pad away from said ring will draw out said portion of said liquid in a film and initiate formation of said film in the opening dellined by said ring.

12. A device as claimed in claim 11 further comprising:

means biasing said pad toward said ring-engaging position.

13. A device as defined in claim 11 wherein said pad comprises:

a hollow supporting member having a peripheral flange formed thereabout of larger diameter than said ring; and

a resilient membrane of smooth, wettable characteristics stretched over said flange of said supporting member for flushed abutment of the rearward, downstream face of said ring, said ring being adapted to be engaged by said membrane in an unsupported region of said membrane defined within said peripheral liange.

14. A device as defined in claim 13 wherein said hollow support member further comprises:

an inner concentric flange smaller in diameter than the opening in said ring;

said pad being mounted to be engageable with said ring in substantial coaxial alignment therewith whereby said ring is engaged by said membrane and the unsupported annular region of said membrane which is defined between said inner and outer flanges of said support member.

15. A device as defined in claim 13 wherein said membrane comprises:

a balloon-like member stretched about said support member.

16. A device as defined in claim 15 further comprising:

said support member having at least one vent hole formed therein to preclude entrapment of an excess volume of air within said covered support member to avoid bulging of said membrane.

17. A device as defined in claim 11 wherein said means Y mounting said pad for said movement toward and away from said ring comprises:

an arm pivotally mounted, at one end thereof, to said device below said bubble forming ring for pivotal movement of the other free end of said arm toward and away from said ring; and

means mounting said pad to said free end of said arm.

18. A device as defined in claim 17 wherein said pad is mounted to said end of said arm for limited universal movement thereon to enable said pad to self seat and flush abutting engagement with said ring.

19. A device as defined in claim 17 further comprising:

means biasing said arm for pivotal movement toward said ring.

20. A device as defined in claim 19 further comprising:

a bracket having a forward end and a rearward end;

means mounting said pivot to said rearward end of said bracket;

a clevis including a pair of clevis plates supported in embracing relation to said bracket and being pivoted to said bracket at said pivot pin;

means mounting said ar-m to said clevis for pivotal movement in unison therewith about said pivot;

said bias means comprising an endless elastic element wrapped about and retained at the forward edge of said bracket, said elastic elements including a pair 10 of rearwardly extending strands embracing said bracket along its sides, each strand of said elastic passing over the edge of its associated clevis plate; said edges of said clevis plate having grooves formed therein to receive and retain the strands of said elastic;

the rear end of said elastic being looped about and connected to said arm.

21. A device as claimed in claim 20 further comprising:

a stop element mounted to and between said clevis plates for engagement with the edge of said bracket to limit the extent of pivotal movement of said arm away from said ring.

22. A device as defined in claim 20 further comprising:

means enabling said bracket to be Imounted to a vehicle.

23. A device for generating bubbles from a hlm-forming liquid, continuously and repetitively comprising:

a ring adapted to be wetted by said liquid and to support said liquid in a film across the opening defined by said ring;

means for supporting said ring in a position in which a stream of air may be directed toward said ring along a path lwhich is substantially normal to the plane in which said ring supports said film whereby said air stream may cause said supported film to be blown into a bubble and discharged from said ring;

ymeans for communicating said liquid from a source thereof to the surface of said ring in a steady, continuous fiow and at a flow rate which is at least suf- 'ficient to replenish the quantity of said liquid which is used in the formation of said bubbles, said replenishment being sufficient to permit continuous regeneration of said film within said ring after each bubble is discharged whereby said bubbles will be generated and emitted from said ring continuously in response to continuation of said air stream;

an air tube having a forward, inlet end to receive and ingest air and a rearward, outlet end, to eject said ingested air, said tube being adapted to direct said ingested air in substantially laminar flow within said tube and along a direction that extends substantially normal to the plane in which said ring supports said `film of liquid; and

said ring being mounted centrally within said tube at the rearward, outlet end thereof.

24. A device as defined in claim 23 wherein said tube is tapered rearwardly to increase the velocity of the air as it passes through said tube.

25. A device as defined in claim 24 further comprising:

a ymounting bracket formed integrally with said device and being adapted to support said device so that the central axis of said tube is disposed in a substantially horizontal orientation and in which the upper region of said rearwardly tapered tube is inclined rearwardly and downwardly;

said source of liquid comprising a tank secured to the upper, downwardly and rearwardly inclined surface of said tube whereby said tank is oriented along a downwardly and rearwardly directed incline;

said means for communicating said liquid from said source comprising a tube connected to said tank at the rearward end thereof, said tube leading to said bubble-forming ring whereby liquid contained within said tank will tend to flow downwardly and rearwardly within said tank toward said tube to permit full exhaustion of the liquid within said tank.

26. A method of generating a continuous stream of bubbles from a film-forming liquid comprising;

providing a ring adapted to be wetted by said liquid and to support said liquid in a film extending across the opening defined by said ring;

directing a stream of said liquid to the surface of said ring in a continuous, steady tiow and at a rate which l l is sufficient to replenish the quantity of liquid which is used in the formation of said bubbles; generating a stream of air toward said ring and along a direction which is substantially normal to the plane in which said ring supports said film whereby a continuous steady stream of bubbles may be emitted downstream of and from said ring during continuation of said air stream and said supply of liquid; confining the flow of said air within a tube; positioning said ring within the rearward, downstream end of said tube and in an orientation which is substantially normal to the direction of ow in which said tube confines said air stream; and

i2 increasing the air speed within said tube as said air approaches said ring.

References Cited UNITED STATES PATENTS 2,720,723 10/1955 Peretti 46-7 3,002,314 10/1961 Brottman 46-6 3,109,255 ll/1963 Hein 46-7 3,210,790 10/1965 Neumann 46-7 X 3,295,248 1/1967 Knerr et al. 46-6 LOUIS G. MANCENE, Primary Examiner D. L. WEINHOLD, JR., Assistant Examiner 

